Enlarged natural gas pipeline proposed for N.E.

A Houston pipeline company has begun exploring the expansion of a major regional pipeline to bring abundant supplies of natural gas to New England from nearby shale formations, a move that could help lower heating and electricity costs here.

Spectra Energy Corp. estimates that increasing pipeline capacity in Southern New England by about 15 percent would save gas and electric customers – including roughly 3 million in Massachusetts – up to $651 million a year. It would allow the area to further benefit from the boom in natural gas production inPennsylvania and New York, although there are no estimates yet on the potential effect on individual bills.